For middle-aged women struggling with their weight, a recent spate of scientific findings sounds too good to be true. And they may be, researchers caution. Studies in mice indicate that a single hormone whose levels rise at menopause could be responsible for a characteristic redistribution of weight in middle age to the abdomen, turning many women from “pears” to “apples.” At the same time, the hormone may spur the loss of bone. The work began when Mone Zaidi, MD, PhD, professor of endocrinology, diabetes and bone disease at the Icahn School of Medicine at Mount Sinai became curious about whether a reproductive hormone, follicle-stimulating hormone, affects bone density. Dr. Zaidi reasoned that this could be a culprit of bone loss. So he and his colleagues created an antibody that blocked FSH in female mice whose ovaries have been removed. But in Dr. Zaidi’s lab, the mice that received the antibody did not develop fat-filled bone marrow - and, to his enormous surprise, they lost large amounts of fat.